Improvement in reverberatory furnaces



W. cHxsHoLM. @E VERBER'AT'ORY FURNACE.

No.172,554. Patented un. z5, 1876.

N.PE1ERS` FHOTOL\THOGRAPHER. WASHINGTON. n.6.

UNITED VS'I'Atras PATENT FFICE.

WILLIAM oHIsHoLM, or CHIUAGO, ILLINOIS.

IMPROVEMENT IN REVERBERATORvI-'URNACES- Specification forming part ofLetters Patent No. 172.5511, dated January 25, 1876; application filedDecember 2, 187:3.

To all whom lt may concern:

Be it known that I, WILLIAM CHIsHoLM, of Chicago, county of Cook, Stateof Illinois, have invented or discovered a new and useful Improvement inMetallurgie and Steam-Boiler Furnace 5 and I do hereby declare thefollowing to be a full, clear, concise, and exact description thereof,reference being hadA to the accompanying drawing making a part of thisspecification, in which-like letters indieatin g like parts- Figure l isa side eleva-tion of my improved metallurgie and boiler furnace. Fig. 2is a longitudinal vertical section thereof. A Fig. 3 is a transversevertical section through the line m x, Fig. 2. Fig. 4 is a like sectionin the line y y, Fig. 2; and Fig. 5 is a perspective view of -one of theperforated bricks employed.

My improvement relates to an improved construction of reverberatoryfurnace for heating, reheating, or otherwise treating metals at hightemperatures, and in connect-ion therewith of a steam-generator, for thegeneration of steam by the use of the otherwise waste heat and productsof combustion from the furnace.

In the accompanying drawing, I have shown two fire-chambers,- A A', andtwo reverberatory chambers, B B. Beyond these the number may beincreased at pleasure by a duplication of the devices shown. The firstfire-chamber A is of the usual or any suitable construction, withunderlying grate-bars a, ash-pit C, closed by doors c; also, with abridge-wall, a2, on the other side of which is the reverberatory chamberB of any desired size or construction.

In the use for which I especially design itthat is, for heating orreheating metals preparatory to working orreworking-I prefer to make itof considerable length, and provide a num ber of doors, I), throughwhich the charges of metal may be introduced and removed, whether in theshape of bars, slabs, plates, blooms, ingots, billets, faggots, bundles,Src. At the opposite end of the chamber B, but with an intermediatebridge-wall, b2, I make the sec-v ond lire-chamber A with, bypreference, about half the capacity of the rst, more or less, and withlike grate-bars al underlying ash-pit C', closed by doors, as before,and a bridge-wall, a3, between it and the next reverberatory chamber B.This has a like series of doors, D', as before described, and the heat,gases, and other product-s of combustion not consumed pass up by andalong fines g It in contact With steam-generators H El, one or more, ofany desired' construction, and thence to the stack h.

In order Vto facilitate and render more perfeet and complete thecombustion of the fuel, particularly where soft or bituminous coal isemployed, I introduce heated air at various Y points. Ihis air is drivenin by any suitable blast through a trunk-pipe, p. From this a branch, d,leads to the ash-pit G, to furnish under the desired blastepressure therequired amount of oxygen to the fire at that point, and another likebranch, d1, furnishes a like supply to the ash-pit C. A third branch,d2, leads to a hollow air box or chamber, e, preferably made ofcast-iron, and which is arranged directly or nearly over the lire-bridgea2, and in line therewith transversely across the furnace. A fourthbranch, d3, leads to a like air box or chamber, e', arranged in likemanner over the bridge-Wall a3. The lower side of each chamber e or e'is closed by perforated bricks, tiles, or tuyeres s, one of which isshown in enlarged view in Fig. 5. These bricks are perforated in adiagonal or inclined direction, as shown, and are so set that the holesshall discharge or supply air downward and forward in the direction ofthe line of draft. As they are exposed to the action of the heat passingover the bridge-wall they are raised to and kept at a high temperature,so that the air becomes heated thereby before it enters theworkingchamber. rIhe capacity of the boxes or chambers e e', relativelyto the aggregate area of the perforations, is such that the air will beretained or stored therein long enough to be heated, so that, afterpassing through the perforations, and on entering the working-chambers,it will be at or but a little below furnace-heat. The result of theadmission of air at such points and under such conditions,` will bereadily understood by those skilled in the art, and need not be furtherexplained. At the second furnace, and intermediate between thebridge-walls b2 and c3, I make the cover of the furnace with an invertedbridge-wall or low arch, n, whereby the gases and other products ofcombustion which mayl have reached that point unconsumed will bedeflected downward to or toward the second fire in the chamber A', so asstill further to facilitate and insure their combustion.

In order to secure like useful results in the ue h I carry branch pipesu u', one or more, from the trunk p transversely across beneath suchllue h, and make therein a slit, c, so arranged that a thin layer orstratum of air shall be projected therefrom upward and forward in theline of the draft. It will be observed that here, as also in themetallurgie furnace, the direction of the injected blasts is such as notonly to increase combustion by direct action, but also such as todeflect the heat, heated gases, &c., to or toward the point, place, orobject at or on which the action of the heat is desired.

The improvements herein described, so far las they are applicable toother furnaces, may be used in connection therewith, and the number ofthe furnaces and working-chambers, with the appliances described asbelonging to each, may be increased to any desired practical extent. Ithus make a continuous series of furnaces and Working-chambers in thesame line of draft, and utilize the othewise waste products ofcombustion from the last of the series in generating steam as a motivepower to drive the mill machinery.

I claim herein as 'my invention-` 1. A series of two or morelire-chambers, A A', in combination with a corresponding number ofmetallurgie working-chambers, one between each two fire-chambers, andone be' vond the last fire-chamber, with a continuous draft through theseries, substantially as and for the purposes set forth. f

Y 2. In combination with the series of alternately arrangedfire-chambers and workingchambers, having a continuous draft throughall, a series of air-blast pipes for supplying air to each fire-chamberand to each workingchamber, substantially as and for the purposes setforth.

3. The described system of fire-chambers, working-chambers, andair-supply pipes, series of alternately arranged firechambers andWorking-chambers, having acontinuous draft through all, a flue, h,arrangedL to conduct the waste productsof combustion from the lastworking-chamber along in contact with one or more steam-generators, andair-blast pipes to supply additional air in s uch iiue h, substantiallyas and for the purposes set forth.

4. In combination with the second, or other subsequent tire-chamber, A',in a series of firechambers, an inverted bridge-wall or low arch, n, andside bridge-walls b2 and a3, relatively arranged and operatingsubstantially in the manner and for the purposes set forth.

WILLIAM CHISHOLM.

Witnesses: l

J. B. STUBBS, W. O. RUNYON.

